Abstract:

An endoluminal prosthesis with a moveable fenestration including a tubular
graft body having a proximal end, a distal end, a surface plane at least
one fenestration having a perimeter disposed in a sidewall of the tubular
body between the proximal end and the distal end, a first biocompatible
graft material, and a second biocompatible graft material adjacent to and
surrounding the perimeter of the at least one fenestration. The second
biocompatible graft material has at least one characteristic different
from the first biocompatible graft material and is more flexible than the
first biocompatible graft material and is movable relative to the surface
plane of the tubular graft body.

Claims:

1. An endoluminal prosthesis, comprising:a tubular graft body comprising:a
proximal end;a distal end;a surface plane;at least one fenestration
having a perimeter disposed in a sidewall of the tubular body between the
proximal end and the distal end;a first biocompatible graft material;
anda second biocompatible graft material adjacent to and surrounding the
perimeter of the at least one fenestration;where the second biocompatible
graft material has at least one characteristic different from the first
biocompatible graft material, andwhere the second biocompatible material
is more flexible than the first biocompatible graft material and is
movable relative to the surface plane of the tubular graft body.

2. The endoluminal prosthesis of claim 1 where the second biocompatible
graft material lies in a different plane than the surface plane.

3. The endoluminal prosthesis of claim 1, where the second biocompatible
graft material is in a radially telescoping relationship relative to the
surface plane of the tubular graft body.

4. The endoluminal prosthesis of claim 1, where the second biocompatible
graft material is defined by a woven fabric comprising yarns aligned in a
first direction interwoven with yarns aligned in a second direction,
where the number of yarns aligned in the first direction are increased
and then decreased while the yarns in the second direction are held
constant such that a protrusion is formed in the area of the tubular body
comprising the fenestration.

5. The endoluminal prosthesis of claim 4, wherein the yarns aligned in the
first direction comprise warp yarns, and the yarns aligned in the second
direction comprise weft yarns.

6. The endoluminal prosthesis of claim 5, where the second biocompatible
graft material comprises between about 50 and about 300 weft yarns per
inch and between about 50 and about 300 warp yarns per inch.

7. The endoluminal prosthesis of claim 4, where the second biocompatible
graft material is composed of yarn having a higher denier than the first
biocompatible graft material of the main body.

8. The endoluminal prosthesis of claim 4, where the textile yarns in the
first direction comprise biocompatible polyurethane.

9. The endoluminal prosthesis of claim 1, where density of the second
biocompatible graft material is equal to the density of the first
biocompatible graft material.

10. The endoluminal prosthesis of claim 1, where density of the second
biocompatible graft material is greater than the density of the first
biocompatible graft material.

11. The endoluminal prosthesis of claim 1, where the second biocompatible
graft material comprises a tube having a first end and a second end.

12. The endoluminal prosthesis of claim 1, where the second biocompatible
graft material has a diameter that is at least 10% greater than the
diameter of the tubular graft body.

13. The endoluminal prosthesis of claim 12, where the second biocompatible
graft material has a diameter of about 2 to about 10 millimeters.

14. An implantable prosthesis for treatment of a main vessel defect near
one or more branch vessels, comprising:a graft comprising a first
biocompatible graft material forming a tubular main body defining a lumen
with a proximal end, a distal end, and a surface plane;at least one
fenestration having a perimeter positioned intermediate the proximal and
distal ends disposed within a sidewall of the main body, the sidewall
comprising a second biocompatible graft material adjacent to and
surrounding the fenestration, the second biocompatible graft material
having at least one characteristic different from the first biocompatible
material and is defined by a woven fabric comprising yarns aligned in a
first direction interwoven with yarns aligned in a second direction,
where yarns aligned in the first direction are increased and decreased
while the yarns in the second direction are held constant to form a
protrusion;where the second biocompatible graft material is of a greater
flexibility than the first biocompatible material such that movement of
the fenestration relative to the surface plane of the main graft is
facilitated and where the second biocompatible graft material lies in a
different plane than the surface plane.

15. The prosthesis of claim 14, where the second biocompatible graft
material is in a radially telescoping relationship relative to the
surface plane of the tubular graft body.

16. The prosthesis of claim 14, where density of the second biocompatible
graft material is greater than the density of the first biocompatible
graft material.

17. The prosthesis of claim 14, where the at least one fenestration is
comprised of a tube having a first end and a second end.

18. The prosthesis of claim 14, where the second biocompatible material
has a diameter that is at least 10% greater than the diameter of the
tubular graft body.

19. The prosthesis of claim 18, where the second biocompatible graft
material has a diameter of about 2 to about 10 millimeters.

20. A method of producing an endoluminal prosthesis, comprising the steps
of:providing textile yarns of a first biocompatible graft material to be
aligned in a first direction and a second direction;weaving the textile
yarns to produce a woven graft having a surface plane;introducing textile
yarns of a second biocompatible graft material in the first direction
while keeping the number of textile yarns in the second direction
constant;withdrawing the added textile yarns in the first direction at
the same rate to create a protrusion; andcreating a fenestration through
the protrusion, where the second biocompatible material is adjacent to
and surrounding the fenestration and is moveable relative to the surface
plane of the woven graft.

Description:

[0001]This application claims the benefit of priority from U.S.
Provisional Application No. 61/093,202, filed Aug. 29, 2008, which is
incorporated by reference.

TECHNICAL FIELD

[0002]This invention relates to endoluminal medical devices for
implantation within the human or animal body for treatment of
endovascular disease.

BACKGROUND OF THE INVENTION

[0003]The functional vessels of human and animal bodies, such as blood
vessels and ducts, occasionally weaken or even rupture. For example, the
aortic wall can weaken, resulting in an aneurysm.

[0004]One surgical intervention for weakened, aneurismal, or ruptured
vessels involves the use of an endoluminal prosthesis to provide some or
all of the functionality of the original, healthy vessel and/or preserve
any remaining vascular integrity by replacing a length of the existing
vessel wall that spans the site of vessel failure. Stent grafts for
endoluminal deployment are generally formed from a tube of a
biocompatible material in combination with one or more stents to maintain
a lumen. Stent grafts effectively exclude the defect by sealing both
proximally and distally the defect, and shunting blood through its
length.

[0005]In many cases, however, the damaged or defected portion of the
vasculature may include a branch vessel. For example, in the case of the
abdominal aorta, there are at least three major branch vessels, including
the celiac, mesenteric, and renal arteries, leading to various other body
organs. Thus, when the damaged portion of the vessel includes one or more
of these branch vessels, some accommodation must be made to ensure that
the prosthesis does not block or hinder blood flow through the branch
vessel.

[0006]Attempts to maintain blood flow to branch vessels have included
providing one or more fenestrations or holes in the side wall of the
prosthesis. Conventionally, a balloon expandable bare stent is deployed
into the renal arteries through the fenestration in the main graft to
assure alignment is maintained while the stent-graft is being delivered
(e.g., manipulated) and continues to maintain patency post-procedure. The
arterial tree is constantly under pulsatile motion due to the flow of
blood through the arteries. Thus, the deployed bare metal secondary stent
is often under severe and complicated loading conditions which must be
borne entirely through the narrow interface presented by fenestrated
prosthesis and the bare secondary stent. These conditions may cause
deterioration of the secondary stent, and may put the patient at risk of
injury. Furthermore, since conventional fenestrated grafts have a fixed
interface, there is little room for error when deploying the prosthesis
for treatment of the aneurysm. The deployment of the prosthesis has to be
extremely precise to assure that the fenestrations are aligned with the
branch vessels. If these branch vessels are blocked by the prosthesis,
the original blood circulation is impeded, and the patient can suffer.
The blockage of any branch vessel is usually associated with unpleasant
or even life-threatening symptoms.

SUMMARY

[0007]One aspect of an endoluminal prosthesis including a tubular graft
body having a proximal end, a distal end, a surface plane, at least one
fenestration having a perimeter disposed in a sidewall of the tubular
body between the proximal end and the distal end, a first biocompatible
graft material, and a second biocompatible graft material adjacent to and
surrounding the perimeter of the at least one fenestration. The second
biocompatible graft material has at least one characteristic different
from the first biocompatible graft material and is more flexible than the
first biocompatible graft material and is movable relative to the surface
plane of the tubular graft body.

[0008]In another aspect, an implantable prosthesis for treatment of a main
vessel defect near one or more branch vessels includes a graft comprising
a first biocompatible graft material forming a tubular main body defining
a lumen with a proximal end, a distal end, and a surface plane, at least
one fenestration having a perimeter positioned intermediate the proximal
and distal ends disposed within a sidewall of the main body, the sidewall
comprising a second biocompatible graft material adjacent to and
surrounding the fenestration, the second biocompatible graft material
having at least one characteristic different from the first biocompatible
material and is defined by a woven fabric comprising yarns aligned in a
first direction interwoven with yarns aligned in a second direction,
where yarns aligned in the first direction are increased and decreased
while the yarns in the second direction are held constant to form a
protrusion. The second biocompatible graft material is of a greater
flexibility than the first biocompatible material such that movement of
the fenestration relative to the surface plane of the main graft is
facilitated and where the second biocompatible graft material lies in a
different plane than the surface plane.

[0009]In yet another aspect, a method of producing an endoluminal
prosthesis graft, including the steps of: providing textile yarns of a
first biocompatible graft material to be aligned in a first direction and
a second direction, weaving the textile yarns to produce a woven graft
having a surface plane, introducing textile yarns of a second
biocompatible graft material in the first direction while keeping the
number of textile yarns in the second direction constant, withdrawing the
added textile yarns in the first direction at the same rate to create a
protrusion, and creating a fenestration through the protrusion, where the
second biocompatible material is adjacent to and surrounding the
fenestration and is moveable relative to the surface plane of the woven
graft.

[0010]The second biocompatible material may be the same material used for
the graft or a different material so long as the graft material
surrounding the fenestration has sufficient give or flexibility to permit
a branch vessel device inserted through the fenestration to move relative
to the fenestration in response to biological or other forces. For
example, the second biocompatible material may comprise a graft material
of a heavier denier than the graft material of the main body to provide
more durability to the flexible fenestration. In one example, the graft
material surrounding the fenestration may be a flexible, tapered sleeve
integrally formed into the graft material.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0011]FIG. 1 depicts a prosthesis with a protrusion of graft material.

[0018]Unless defined otherwise, all technical and scientific terms used
herein have the same meaning as commonly understood to one of ordinary
skill in the art to which this invention belongs.

[0019]The terms "distal" and "distally" are intended to refer to a
location or direction that is, or a portion of a device that when
implanted is further downstream in the direction of or with respect to
blood flow. The terms "proximal" and "proximally" are intended to refer
to a location or direction that is, or a portion of a device that when
implanted is further upstream in the direction of or with respect to
blood flow.

[0020]The term "prosthesis" means any replacement for a body part or
function of that body part. It can also mean a device that enhances or
adds functionality to a physiological system.

[0021]The term "tubular" refers to the general shape of an endoluminal
device which allows the module to carry fluid along a distance or fit
within a tubular structure such as an artery. Tubular prosthetic devices
include single and both branched and bifurcated devices.

[0022]The term "endoluminal" refers to or describes objects that can be
placed inside a lumen or a body passageway in a human or animal body. A
lumen or a body passageway can be an existing lumen or a lumen created by
surgical intervention. As used in this specification, the terms "lumen"
or "body passageway" are intended to have a broad meaning and encompasses
any duct (e.g., natural or iatrogenic) within the human body and can
include a member selected from the group comprising: blood vessels,
respiratory ducts, gastrointestinal ducts, and the like. "Endoluminal
device" or "endoluminal prosthesis" thus describes devices that can be
placed inside one of these lumens.

[0023]The term "stent" means any device or structure that adds rigidity,
expansion force or support to a prosthesis. A stent is used to obtain and
maintain the patency of the body passageway while maintaining the
integrity of the passageway. Also, the stent may be used to form a seal.
The stent may be located on the exterior of the device, the interior of
the device, or both. A stent may be self-expanding, balloon-expandable or
may have characteristics of both. A variety of other stent configurations
are also contemplated by the use of the term "stent."

[0024]The term "yarn" refers to a length of a continuous thread or strand
of one or more filaments or fibers, with or without twist, suitable for
weaving, knitting or otherwise intertwining to form a textile fabric.

[0025]The term "graft" or "graft material" describes an object, device, or
structure that is joined to or that is capable of being joined to a body
part to enhance, repair, or replace a portion or a function of that body
part. A graft by itself or with the addition of other elements, such as
structural components, can be an endoluminal prosthesis. The graft
comprises a single material, a blend of materials, a weave, a laminate,
or a composite of two or more materials. The graft can also comprise
polymer material that may be layered onto the mandrel of the present
invention. Preferably, polymers of the present invention, although added
in layers onto the mandrel, after curing, result in one layer that
encapsulates a stent or woven graft. This also aids in decreasing the
incidence of delamination of the resulting endovascular prosthesis. A
stent may be attached to a graft to form a "stent graft."

[0026]The term "branch vessel" refers to a vessel that branches off from a
main vessel. Examples are the celiac and renal arteries which are branch
vessels to the aorta (i.e., the main vessel in this context). As another
example, the hypogastric artery is a branch vessel to the common iliac,
which is a main vessel in this context. Thus, it should be seen that
"branch vessel" and "main vessel" are relative terms.

[0027]"Longitudinally" refers to a direction, position or length
substantially parallel with a longitudinal axis of a reference, and is
the length-wise component of the helical orientation.

[0028]"Circumferentially" refers to a direction, position, or length that
encircles a longitudinal axis of reference. Circumferential is not
restricted to a full 360° circumferential turn nor a constant
radius.

[0029]The terms "patient," "subject," and "recipient" as used in this
application refer to any mammal, especially humans.

[0030]Prostheses with moveable fenestrations are provided comprising a
wall made from graft material formed into a tube. A lumen extends
longitudinally throughout the prosthesis. The moveable fenestration is
configured such that it permits a branch prosthesis that is inserted into
and through the fenestration to move relative to the plane of the wall of
the main prosthesis. The moveable fenestration may be a flexible
fenestrated sleeve.

[0031]In some aspects, the flexible fenestrated sleeve is tapered.
Further, the flexible fenestrated sleeve may have ability to move
telescopically. Once a secondary branch stent is deployed into a branch
vessel through the flexible fenestrated sleeve, the flexible fenestrated
sleeve works to maintain alignment of the fenestration and a branch
vessel.

[0032]FIG. 1 illustrates one aspect of a prosthesis 10 in accordance with
the present invention. The prosthesis 10 comprises a tubular graft body
12 having a surface plane configured to be placed within a diseased
vessel of a patient. The prosthesis 10 is comprised of a first
biocompatible graft material 16 and includes a proximal end and a distal
end. The graft material 16 may be constructed from a biocompatible
textile fabric, a polymer, biomaterial, or a composite thereof. Examples
of biocompatible materials from which textile graft material can be
formed include polyesters, such as polyethylene terephthalate);
fluorinated polymers, such as polytetrafluoroethylene (PTFE) and fibers
of expanded PTFE; and polyurethanes. Preferably, the graft material 16 is
a woven polyester. More preferably, the graft material 16 is a
polyethylene terephthalate (PET), such as DACRON® (DUPONT,
Wilmington, Del.) or TWILLWEAVE MICREL® (VASCUTEK, Renfrewshire,
Scotland).

[0033]In this aspect, the tubular graft body 12 includes a sidewall 14
containing a protrusion 18 of a second biocompatible graft material 17.
The protrusion 18 is integrally formed from the body of the tubular graft
body 12, and extends outward radially in a bubble like formation. The
protrusion 18 is comprised of a second biocompatible graft material and
may be created during the weaving process used to create the tubular
graft body 12. The second biocompatible graft material may have at least
one characteristic different than the first biocompatible graft material.
In addition, the second biocompatible graft material may be more flexible
than the first biocompatible graft material. The prosthesis 10 may
comprise any kind of weave. For example, the tubular graft body 12 may
include, but is not limited to, weaves such as plain weaves, basket
weaves, rep or rib weaves, twill weaves (e.g., straight twill, reverse
twill, herringbone twill), satin weaves, and double weaves (e.g.,
double-width, tubular double weave, reversed double weave). Desirably,
the weave comprises a tubular double layer weave. The tubular graft body
12 and the protrusion 18 may be woven in any suitable manner. For
example, the fabric may be woven on a table loom, a floor loom, a
jacquard loom, a counterbalance loom, a jack loom, or an upright loom.
Desirably, the fabric is woven on a floor loom. The fabric may have any
configuration possible, but preferably has warp and weft yarns. In one
aspect, both the warp yarns and the weft yarns are textile yarns.

[0034]During the weaving process to create the graft, the sett and pick
count are kept constant. The sett may be between about 50 and about 300
ends per inch and the pick count may be between about 50 and about 300
picks per inch. An "end" refers to an individual warp yarn, and a "pick"
refers to an individual weft yarn. In one aspect, the textile graft
comprises a plain weave having 150 ends per inch and 250 picks per inch.

[0035]In order to create the protrusion 18, the number of warp yarns used
while weaving the prosthesis 10 is increased in the region where the
protrusion 18 is desired. While the additional warp yarns are weaved into
the prosthesis 10, the number of weft yarns is kept constant. By
increasing the number of warp yarns while holding the number of weft
yarns constant, the second biocompatible graft material 17 expands
outwardly in the radial direction. The number of warp yarns is increased
until a pre-determined diameter has been reached. The predetermined
diameter of the protrusion 18 may range from about 2 mm to about 10 mm.
Once the desired diameter for the protrusion 18 is reached, the number of
warp yarns introduced into the weaving apparatus is decreased until the
number of warp yarns is equal to the number of weft yarns used to form
the remainder of the graft 12. During this weaving process, the sett and
pick count are kept constant due to the increasing diameter of the graft
12 in the area of the protrusion 18. Further, the density of the
protrusion 18 is kept constant by weaving the weft yarns at the same
speed.

[0036]In another aspect, the density of the protrusion 18 may be altered
based on the needs of the patient. For example, one may achieve a
protrusion 18 of an increased density in the direction of the warp yarns
by weaving the weft yarns at a slower speed and by changing the sett and
pick count of the weave. This increased density provides increased
structural support for the graft 12, which can benefit a patient
suffering from vessels having an advanced diseased state. Alternatively,
the density of the protrusion 18 in the direction of the warp yarns may
be decreased by weaving the weft yarns at a faster speed. Further, the
change in density allows for increased control of the desired shape of
the protrusion 18.

[0037]In other aspects, yarns having a heavier denier may be used to
create the protrusion 18 in order to increase the durability of the
protrusion 18. For example, the graft material 16 of the tubular graft
body 12 may be comprised of a plurality of yarns having a denier of about
100. In order to provide added strength and durability for the flexible
sleeve, the second biocompatible graft material 17 comprised of a
plurality of yarns having a denier of about 120 may be weaved into the
tubular graft body to form the protrusion 18 during the process used to
produce the prosthesis. The protrusion 18 may also be tapered in order to
generate a cone effect at the position of the fenestration.

[0038]FIG. 2 illustrates one aspect of a tubular graft body 12 containing
a fenestration 22. The fenestration 22 has a perimeter and is disposed
through the protrusion 18 and the sidewall 14 such that the fenestration
22 is in fluid communication with a lumen 20 of the graft body 12. In
some aspects, the fenestration 22 is created through the protrusion 18 by
applying heat to the center of the protrusion 18 at a temperature of at
least 260° C. The application of heat causes the fibers of the
graft material 16 to melt together, which helps prevent fraying.
Alternatively, the fenestration 22 may be created by cutting the
protrusion 18 in its center in order to form an opening for the
fenestration 22. In this aspect, an adhesive may be applied to edges of
the perimeter of the fenestration 22 to prevent the fibers from fraying.
Thus, the second biocompatible graft material 17 is adjacent to and
surrounding the perimeter of the fenestration 22, and the second
biocompatible graft material may be in a different plane than the surface
plane of the tubular graft body 12. The second biocompatible graft
material 17 surrounding the fenestration 22 is moveable relative to the
surface plane of the tubular graft body 12. The diameter of the
fenestration 22 may be modified depending on the size of the patient's
vessels. The diameter of the fenestration 22 may range from about 2 mm to
about 10 mm. Preferably, the second biocompatible graft material
surrounding the fenestration 22 has a diameter that is at least 10%
greater than the diameter of the graft.

[0039]As shown in FIG. 2, a nitinol ring 24 may be placed about the
perimeter of the fenestration 22 in order to prevent it from closing. The
nitinol ring 24 may be secured about the perimeter of the fenestration 22
by suture material. In other aspects, the fenestration 22 may be
prevented from closing by placing a seam comprised of biocompatible
materials, such as suture material, about the perimeter of the
fenestration 22. Any excess material suture material present after
creating the seam may be removed by cutting the material within the
circumference of the fenestration 22.

[0040]The second biocompatible graft material 17 surrounding the
fenestration 22 may be in a radially telescopic relationship with respect
to the surface plane of the tubular graft body 12. As such, the second
biocompatible graft material 17 surrounding the fenestration 22 may be
configured to move telescopically within a certain range. The telescopic
range 26 spans from the edge of the fenestration 22 to the sidewall 14 of
the tubular graft body 12. The telescopic range 28 allows the moveable
fenestration 22 to be pushed flush with the diameter of the tubular graft
body 12. Once the fenestration 22 is flush with the wall 14 of the
tubular graft body 12, a wrinkle is formed by the second biocompatible
graft material 17 adjacent to and surrounding the fenestration 22. This
wrinkle provides for the relative movement of the fenestration 22 and the
tubular graft body 12 without transmitting significant load to the
fenestration 22. This movement reduces the amount of stress applied to a
secondary branch stent when it is deployed into a branch vessel.

[0041]In some aspects, the second biocompatible material forming the
protrusion 18 or area surrounding the fenestration 22 may be comprised of
biocompatible materials that are different than the first biocompatible
material used to form the tubular graft body 12. Examples of suitable
biocompatible materials include: polyurethane, silicone infused
polyurethane, such as Thoralon® (Thoratec, Pleasanton, Calif.), or
Biospan®, Bionate®, Elasthane®, Pursil® And Carbosil®
(Polymer Technology Group, Berkeley, Calif.).

[0042]FIGS. 3 and 4 illustrate aspects of a prosthesis for deployment in
the abdominal aorta. As seen in FIG. 3, the prosthesis 10 comprises a
tubular stent graft 30 with a wall 34 and a lumen 32 disposed
longitudinally therein. The tubular stent graft 30 includes a
fenestration 22 disposed through the second biocompatible graft material
added during the weaving process. The fenestration 22 is in communication
with the lumen 32 of the tubular stent graft 30. The prosthesis 10
further comprises a plurality of expandable stents 36 affixed to the wall
34 of the tubular stent graft 30. The expandable stents 36 maintain the
patency of the prosthesis and ensure adequate sealing against the
surrounding vascular tissue. The Z-stent design is preferred for straight
sections of the aorta; it provides both significant radial force as well
as some longitudinal support. In some instances, it may be desirable to
affix some of the stents to the internal surface of the prosthesis. Stent
amplitude, spacing and stagger are preferably optimized for each
prosthesis design. The expandable stents 36 include struts 38 that are
spaced apart from each other. The strut spacing is measured from
peak-to-peak. The peaks 40 of the struts 38 may be staggered for minimal
contact with each other.

[0043]The stent may be formed from nitinol, stainless steel, tantalum,
titanium, gold, platinum, inconel, iridium, silver, tungsten, cobalt,
chromium, or another biocompatible metal, or alloys of any of these.
Examples of other materials that may be used to form stents include
carbon or carbon fiber; cellulose acetate, cellulose nitrate, silicone,
polyethylene teraphthalate, polyurethane, polyamide, polyester,
polyorthoester, polyanhydride, polyether sulfone, polycarbonate,
polypropylene, high molecular weight polyethylene,
polytetrafluoroethylene, or another biocompatible polymeric material, or
mixtures or copolymers of these; polylactic acid, polyglycolic acid or
copolymers thereof; a polyanhydride, polycaprolactone,
polyhydroxybutyrate valerate or another biodegradable polymer, or
mixtures or copolymers of these; a protein, an extracellular matrix
component, collagen, fibrin, or another biologic agent; or a suitable
mixture of any of these. Preferably, the stent is a nitinol or stainless
steel stent. Any of the stents mentioned herein may have barbs to help
decrease prosthesis migration.

[0044]As illustrated in FIG. 3, the fenestration 22 is flush with the
diameter of the tubular stent graft 30. Radiopaque markers 42 may be
placed around the fenestration 22 in order to assist with proper
alignment of the tubular stent graft 30 when deployed within the patient.
The radiopaque markers 42 may be sewn to the wall 34 of the tubular stent
graft 30. Radiopaque materials such as gold, platinum, tungsten, or any
other high density material may be used.

[0045]In another aspect, depicted in FIG. 4, an opening is cut into the
wall 34 of the tubular stent graft 30, and a flexible tube 44 is affixed
about the opening. The tube 44 also includes a first end 46 and a second
end 48, and it may also be tapered. The tube 44 is affixed to the
sidewall 34 of the tubular graft body 30 by suturing the proximal end of
the tube 44 circumferentially about the opening. The second end 48 of the
tube 44 is in communication with the opening. In order to keep the
fenestration in an open configuration, a nitinol ring 26 may be placed
about the second end 48 of the solid tube 44. The second end 48 of the
solid tube 44 may also be maintained in an open configuration by means
other suitable means known by a person of the ordinary skill in the art.

[0046]FIG. 5 depicts an exemplary prosthesis deployed in a patient. The
prosthesis 10 comprising a tubular graft body 12 is deployed in the main
vessel 50 of the patient. The tubular graft body 12 includes a moveable
fenestration 22 in communication with the lumen 20. A secondary branch
prosthesis 54, such as a stent, is deployed into a branch vessel 52 to
maintain the alignment of the flexible fenestration 22 and the branch
vessel 52. The secondary branch prosthesis 54 is formed from
biocompatible material and is comprised of a plurality of stents having
struts 58 that extend circumferentially about a longitudinal axis and
form a lumen 56 extending longitudinally within the secondary branch
prosthesis 54. Examples of acceptable biocompatible metals are discussed
above. The fenestration 22 receives the secondary branch prosthesis 54.
The second biocompatible graft material surrounding the fenestration 22
wrinkles when it is flush with the diameter of tubular graft body 12,
which allows for some movement of the fenestration 22 relative to the
surface plane of the tubular graft body 12 without transmitting direct
force to the secondary branch prosthesis 54.

[0047]FIGS. 6A and 6B illustrate a further aspect of the present
invention. As shown by FIG. 6A, a prosthesis 110 includes a tubular graft
body 112 formed of a first biocompatible graft material comprising a
first fenestration 122 and a second fenestration 123 disposed through the
sidewall 114 of the tubular graft body 112, where a second biocompatible
material 124 is surrounding and adjacent to the first fenestration 122.
The tubular graft body 112 also includes a lumen 120. This aspect is
suitable for implantation in an abdominal aortic aneurysm where two
branch vessels may be occluded during the deployment of the tubular
graft. The second fenestration 123 may be a fixed fenestration or it may
be disposed through a protrusion formed from the weaving of a second
biocompatible graft material. The second fenestration 123 is in
communication with the lumen 120 of the tubular graft body 112.
Radiopaque markers (not shown) may be placed about the flexible
fenestrated sleeve and the second fenestration 123 in order to assist the
physician with placement of the tubular graft body 112.

[0048]The second fenestration 123 may be created in the tubular graft body
112 relative to the location of the first fenestration 122 on the tubular
graft body 112. For example, patients suffering from abdominal aortic
aneurysms may have branch vessels that are not aligned. Thus, in order to
facilitate alignment of the tubular graft body 112 within the vasculature
of the patient, the second fenestration 123 may be formed after the first
fenestration 122 is created from a protrusion comprised of second
biocompatible graft material 124. In addition, the length of the tubular
graft body 112 may also be altered relative to the flexible fenestration
122 in order to configure the tubular graft body 112 with vasculature of
the patient.

[0049]As shown in FIG. 6B, a tubular graft body 112 of the example shown
in FIG. 6A is deployed in the main vessel 50 of the patient to occlude an
aneurysm. The fenestration 122 is flush with the diameter of the sidewall
114 of the tubular graft body 112 creating a wrinkle comprised of the
second biocompatible graft material 124 surrounding the fenestration 122.
Two secondary branch prostheses 54, having a plurality of struts 60 and
having a central lumen 56, are deployed in the branch vessels. The
secondary branch prostheses 54 help maintain alignment of the tubular
graft body 112 to provide for proper blood flow to the branch vessels 52,
62. The secondary branch prostheses 54 are received through the first
fenestration 122 and the second fenestration 123, respectively.

[0050]In some instances, the first fenestration 122 may not be aligned
with the branch vessel 52. In this example, the wrinkle of graft material
of the first fenestration 122 allows for some movement of the first
fenestration 122 relative to the surface plane of the tubular graft body
112 without transmitting direct force to the secondary branch stent 54,
which helps to provide alignment between the first fenestration 122 and
the branch vessel 52.

[0051]Throughout this specification various indications have been given as
to preferred and alternative examples and aspects of the invention.
However, the foregoing detailed description is to be regarded as
illustrative rather than limiting and the invention is not limited to any
one of the provided aspects. It should be understood that it is the
appended claims, including all equivalents, that are intended to define
the spirit and scope of this invention.